import java.util.ArrayList;
import java.util.Collection;

public class Test03 {
    public static void main(String[] args) {
        Collection<String> coll=new ArrayList<>();
        coll.add("aaa");
        coll.add("bbb");
        coll.add("ccc");
        System.out.println(coll);
        /*coll.clear();
        System.out.println(coll);*/
        /*boolean result = coll.remove("aaa");
        System.out.println(result);
        System.out.println(coll);*/
        boolean result1=coll.isEmpty();
        System.out.println(result1);
        boolean result2=coll.contains("aaa");
        System.out.println(result2);
        int len=coll.size();
        System.out.println(len);


    }
}
